The present invention relates in general to hybrid, vertical current injection electro-optical devices and silicon photonics chips that include such electro-optical devices. In particular, the present invention is directed to a hybrid, vertical current injection electro-optical device comprising a current blocking layer, whose refractive index is matched to the effective refractive index of the optical amplification region of the device.
The integration of III-V semiconductor gain materials (e.g., for light sources emitting at datacom and/or telecom wavelengths) in silicon photonics platforms is desired, for example to obtain high-bandwidth optical interconnects. The monolithic integration of III-V optoelectronic devices on silicon (Si), complementary metal oxide semiconductor (CMOS) platforms require shallow stacks of III-V semiconductor gain materials designed for optical amplification, e.g., forming a multiple quantum well, or MQW. The optical modes involved in such structures are typically hybrid modes, i.e., modes that are partially located in the III-V region and partially in the Si waveguide core underneath. The higher the overlap of the mode with the III-V active region, the easier it is to achieve a lasting effect.
In recent years, substantial efforts have been made to achieve satisfactory integration of small electro-optical devices in III-V-based silicon photonics platforms, in order to achieve low-power, on-chip optical interconnects.